Prizes & Awards
My Profile
Active Members
TodayLast 7 Days
more...
|
Resources » Code Snippets » ASP.NET WebForms »
Upload Image and define size
|
Hey, I am presenting a code how to upload an image + check valid extension + create thumbnail + define thumbnail width and height
OK now come to detail, I only allow the .jpg extension, that you can find in the code with comments, you change your required extension, I also check either file has contents are not by simply add if statement
if (nFileLen == 0)
{
Your Message
}
You can change your thumbnail width and height by changing the variable value from 400 hundred to your required integer
intThumbWidth = 400;
intThumbHeight = 400;
In exception you can find the code how to delete a file, you can also make a function to delete a file, and pass the path of server and the file will be deleted from server
Keep in mind I am saving both file in folder, mean thumbnail and the original file, if you want then you can only save the thumbnail
You will find more comments in code, but if you have any problem regarding to this code then please feel free to ask
I am not inserting the code of aspx file, so please note that in aspx file you need just two controls, upload control(ID=filUpload) and label control(ID=lblOutput), if you want to execute this function on clink event of button then you also need to button control and execute UploadImage() function in button click.
public void UploadImage()
{
string sSavePath;
string sThumbExtension;
int intThumbWidth;
int intThumbHeight;
// Set constant values
sSavePath = "~/Images/";
sThumbExtension = "_thumb";
intThumbWidth = 400;
intThumbHeight = 400;
// If file field isn’t empty
if (filUpload.PostedFile != null)
{
// Check file size (mustn’t be 0)
HttpPostedFile myFile = filUpload.PostedFile;
int nFileLen = myFile.ContentLength;
if (nFileLen == 0)
{
lblOutput.Text = "No file was uploaded.";
return;
}
// Check file extension (must be JPG)
if (System.IO.Path.GetExtension(myFile.FileName).ToLower() != ".jpg")
{
lblOutput.Text = "The file must have an extension of JPG";
return;
}
// Read file into a data stream
byte[] myData = new Byte[nFileLen];
myFile.InputStream.Read(myData, 0, nFileLen);
// Make sure a duplicate file doesn’t exist. If it does, keep on appending an
// incremental numeric until it is unique
string sFilename = System.IO.Path.GetFileName(myFile.FileName);
int file_append = 0;
while (System.IO.File.Exists(Server.MapPath(sSavePath + sFilename)))
{
file_append++;
sFilename = System.IO.Path.GetFileNameWithoutExtension(myFile.FileName)
+ file_append.ToString() + ".jpg";
}
// Save the stream to disk
System.IO.FileStream newFile = new System.IO.FileStream(Server.MapPath(sSavePath + sFilename),
System.IO.FileMode.Create);
newFile.Write(myData, 0, myData.Length);
newFile.Close();
// Check whether the file is really a JPEG by opening it
System.Drawing.Image.GetThumbnailImageAbort myCallBack =
new System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback);
Bitmap myBitmap;
try
{
myBitmap = new Bitmap(Server.MapPath(sSavePath + sFilename));
// If jpg file is a jpeg, create a thumbnail filename that is unique.
file_append = 0;
string sThumbFile = System.IO.Path.GetFileNameWithoutExtension(myFile.FileName)
+ sThumbExtension + ".jpg";
while (System.IO.File.Exists(Server.MapPath(sSavePath + sThumbFile)))
{
file_append++;
sThumbFile = System.IO.Path.GetFileNameWithoutExtension(myFile.FileName) +
file_append.ToString() + sThumbExtension + ".jpg";
}
// Save thumbnail and output it onto the webpage
System.Drawing.Image myThumbnail = myBitmap.GetThumbnailImage(intThumbWidth, intThumbHeight, myCallBack, IntPtr.Zero);
myThumbnail.Save(Server.MapPath(sSavePath + sThumbFile));
//imgPicture.ImageUrl = sSavePath + sThumbFile;
// Displaying success information
lblOutput.Text = "File uploaded successfully!";
string CompletePath = "~/Images/" + sThumbFile; //Get folder and FilePath
myThumbnail.Dispose();
myBitmap.Dispose();
// DeleteHDFile();
}
catch (ArgumentException errArgument)
{
// The file wasn't a valid jpg file
lblOutput.Text = "The file wasn't a valid jpg file.";
System.IO.File.Delete(Server.MapPath(sSavePath + sFilename));
}
}
}
public bool ThumbnailCallback()
{
return false;
}
|
Responses
|
| Author: rangasamy 15 Oct 2009 | Member Level: Bronze Points : 0 |
 | | Author: Robin Thomas 18 Nov 2009 | Member Level: Bronze Points : 0 | Thanks nisar for the wonderful code
It workss...............
|
|